Breast Cancer Stages

Breast cancer can be divided into four number stages. The stages of breast cancer take into account the tumour size, whether any lymph nodes are affected, and whether the cancer has spread to other parts of the body.

Stage I Breast Cancer
Stage 1 breast cancer is when the tumour is no more than 2 centimetres across, there are no cancer cells in the lymph nodes in the armpit, and the cancer has not spread elsewhere in the body.

The tumour is greater than 2 cm across, the lymph nodes in the armpit have cancer cells but they have not adhered to each other, and the cancer has not spread elsewhere in the body, or
The tumour is less than 5 cm across, the lymph nodes in the armpit have no cancer cells, and the cancer has not spread elsewhere in the body, or
No tumour was found in the breast, the lymph nodes under the arm have cancer cells but they have not adhered to each other or to other structures, and the cancer has not spread to other parts of the body.
Stage 2B breast cancer means:

The tumour is less than 5 cm across, the lymph nodes in the armpit have cancer cells which are not stuck together, and the cancer has not spread elsewhere in the body, or
The tumour is larger than 5 cm across, the lymph nodes in the armpit have no cancer cells, and the cancer has not spread to other parts of the body.

No tumour is found in the breast, the lymph nodes in the armpit contain cancer cells which have adhered to each other or to other structures, and the cancer has not spread to other parts of the body, or
The tumour is 5 cm across or the less, the lymph nodes under the arm have cancer cells which are stuck together, and the cancer has not spread elsewhere in the body, or
The tumour is more than 5 cm across, the lymph nodes under the arm have cancer cells which have adhered to each other, and the cancer has not spread
Stage 3B breast cancer means:

The tumour in the breast has adhered to the skin or chest wall, the lymph nodes may or may not contain cancer cells, and the cancer cells have not spread.
Stage 3C breast cancer means:

The tumour is any size and has spread to lymph nodes under the arm and breast bone, or to the nodes above or below the collarbone, but the cancer has not spread elsewhere in the body.
Stage 4 Breast Cancer
Stage 4 breast cancer means:

The tumour is of any size.
The lymph nodes may or may not contain cancer cells.
The cancer has spread to other parts of the body.